His Harlem-centered congressional district, once overwhelmingly African American, is now majority Hispanic. He squeaked through his 2012 primary by slightly more than 1,000 votes. Heavyweight endorsements that were once his are going now to his opponent. After nearly 44 years in Congress, the Democrat is trying to hang on to his New York seat and throwing a few elbows in the process.

Rangel, 83, the third-most-senior member of Congress, is embroiled in a primary rematch with state Sen. Adriano Espaillat, 59, whose base is in the district's growing Dominican-American community. In 2012, redistricting kept the same percentage of black voters — 29% — but increased Hispanic voters from 46% to 55%. In the heavily Democratic district, which covers Upper Manhattan and a swath of the Bronx, the primary June 24 is the deciding contest.

Espaillat has had two more years to organize and get his name out and has the backing of former Rangel supporters, including the speaker of the City Council, the Bronx borough president and the city teachers union.

"We're confident that we have the numbers on our side,'' Espaillat says. "People want change.''

Rangel's electoral weakness began in 2010 with an ethics investigation and censure — in part for failing to pay taxes on his vacation home in the Dominican Republic — which cost him the chairmanship of the powerful Ways and Means Committee. In 2012, Rangel was hobbled by back problems and had to use a walker.

He's recovered and is making the rounds, pushing hard on his record as a prodigious legislator, his seniority and his support of the Democratic agenda on immigration. Former president Bill Clinton recorded robocalls on his behalf, and Manhattan Congresswoman Carolyn Maloney is raising money for him.

Endorsements are important if they come with an organization to get voters registered and to the polls, crucial in a midterm election.

The race "will be about who will put the better organization together, whether they have union support or not,'' says Hank Sheinkopf, a New York Democratic consultant. "Sometimes unions perform, and sometimes they don't. The real issue is, is it just time for change?"

On the campaign trail, Rangel is unmistakably a longtime incumbent: At a debate Wednesday, he skipped a standard opening statement. Instead, he pulled out his cellphone and pretended to have a conversation in which he ripped Espaillat for being an ineffective state legislator and called a third candidate, Pastor Michael Walrond, an interloper who doesn't live or vote in the district. (Walrond says he moved into Harlem this year.)

"When this debate is over, we've got to put up,'' Rangel told the debate crowd. "And all I'm saying is, I got the record, and they don't.''

Espaillat is the first Dominican-born member of the state Legislature and would be the first in Congress though he downplays his background. "This isn't West Side Story Sharks vs. Jets,'' he says.

"The Dominican community is much newer to politics in the city. And this is a major historic point for them,'' says political scientist Angelo Falcon of the National Institute for Latino Policy. In light of the Democratic minority in the House and Rangel's ethics trouble, voters may see less rationale for sticking with the dean of the New York delegation — an unofficial title Rangel often mentions. "He doesn't have all the firepower that an incumbent of his years would normally have,'' Falcon says. "That does make him vulnerable.''

Even politicians who support Rangel say a changing of the guard is inevitable.

"Ten years from now, the Congress member from this district is going to be Dominican. Everybody should just get that that is what is going on,'' says David Paterson, who became the state's first African-American governor when he succeeded Eliot Spitzer in 2009.

"What' s happening to a black politician is what used to happen to white politicians, when the (demographics) changed," Paterson says. "The white politician would feel maybe a little hurt because they provided great service to people. And now the people are saying, 'It's not that you're so bad, but we want somebody that looks like us.' ''

Rangel, who won his first election in 1970 by knocking off pioneering black politician Adam Clayton Powell Jr., isn't conceding the point — at least not if that somebody is Espaillat.

"Listen, when Jackie Robinson broke into the major leagues, all of us felt proud,'' he said after Wednesday's debate. "But he was a great player before he got there. They didn't pick him because he was colored.''